Spot Forecast
Issued by NWS Jacksonville, FL

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693
FNUS72 KJAX 100703
FWSJAX

Spot Forecast for MaSF...FFS
National Weather Service Jacksonville FL
303 AM EDT Thu Sep 10 2026

Forecast is based on ignition time of 0800 EDT on September 10.
If conditions become unrepresentative, contact the National Weather
Service.

Please contact our office at (904) 741-4370 if you have questions
or concerns with this forecast.

.DISCUSSION...

Light winds will prevail this morning, but as the east coast
sea breeze develops, the 20-foot winds will turn to the
southeast and east by the noon hour. A few showers may develop
on the sea breeze over St Johns and Flagler counties by 11 AM,
with increased chance of showers and thunderstorms into the early
afternoon hours. These rain chances will remain through the early
evening hours.

Daytime dispersion values both today and Friday will be
poor, at about 23-28. Min RH today and Friday will be above 60
percent. Max heat index about 103-104 both days.

A good chance of scattered showers and storms on Friday
mainly during the afternoon hours.

.TODAY...
TIME (EDT)      8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........22  20  21  25  35  38  53  63  63  62
Weather cov.....                    SCH CHC CHC CHC CHC
Weather type....                    RW  RW  RW  RW  RW
Tstm cov........                        CHC CHC CHC CHC
Chc of pcpn (%).0   0   0   10  10  20  30  40  50  40
Chc of thdr (%).0   0   0   10  10  10  30  40  50  40
Temp............78  80  84  86  88  88  88  88  85  85
RH..............96  94  82  77  72  72  72  72  80  80
Heat index (F)..78  87  95  98  102 102 102 102 97  97
20 FT wind dir..S   SE  S   SE  SE  SE  E   E   SE  SE
20 FT wind spd..2   2   3   6   7   8   9   10  10  10
20 FT wind gust.5   6   7   9   10  12  13  14  14  14
Mix hgt (kft)...0.5 1.2 1.8 2.5 2.4 2.3 2.2 1.9 1.6 1.3
Transp wind dir.S   S   S   S   S   SE  SE  SE  SE  SE
Transp wind spd.5   6   6   7   8   8   9   10  10  10
Dispersion idx..5   9   13  21  23  24  25  23  21  19
LVORI...........6   5   4   3   3   3   3   3   3   3

.TONIGHT...
TIME (EDT)      6PM 7PM 8PM 9PM 10P 11P MID 1AM 2AM 3AM 4AM 5AM
Sky (%).........60  60  57  61  55  51  59  42  33  28  19  33
Weather cov.....CHC CHC SCH SCH
Weather type....RW  RW  RW  RW
Tstm cov........CHC CHC SCH SCH
Chc of pcpn (%).40  40  20  20  10  10  10  10  10  10  0   10
Chc of thdr (%).40  40  20  20  10  10  10  10  10  10  0   10
Temp............84  81  79  78  78  77  77  77  76  76  75  75
RH..............80  85  91  94  94  94  94  94  97  97  97  97
Heat index (F)..94  87  79  78  78  77  77  77  76  76  75  75
20 FT wind dir..SE  SE  SE  S   S   S   S   S   SW  S   S   SW
20 FT wind spd..9   7   7   6   5   5   3   2   2   2   2   2
20 FT wind gust.14  12  10  9   9   8   7   6   5   5   5   5
Mix hgt (kft)...1.1 1.0 0.9 0.7 0.6 0.5 0.5 0.5 0.5 0.5 0.4 0.4
Transp wind dir.SE  S   S   S   S   S   S   S   S   S   SW  SW
Transp wind spd.10  10  10  9   9   9   8   8   8   8   7   6
Dispersion idx..17  14  8   7   6   6   5   5   4   3   3   3
LVORI...........4   4   5   6   6   6   6   6   7   7   7   8

.FRIDAY...
TIME (EDT)      6AM 7AM 8AM 9AM 10A 11A 12P 1PM 2PM 3PM 4PM 5PM
Sky (%).........23  20  23  12  22  17  24  41  52  52  59  66
Weather cov.....                                CHC CHC SCH CHC
Weather type....                                RW  RW  RW  RW
Tstm cov........                                CHC CHC SCH CHC
Chc of pcpn (%).10  10  10  0   0   10  10  10  30  30  20  40
Chc of thdr (%).10  10  10  0   0   10  10  10  30  30  20  40
Temp............75  75  76  79  83  86  88  88  88  87  88  85
RH..............97  97  97  94  85  80  72  75  75  77  72  80
Heat index (F)..75  75  76  79  93  100 102 103 103 101 102 97
20 FT wind dir..SW  SW  SW  S   S   S   SE  SE  SE  SE  SE  SE
20 FT wind spd..2   1   1   2   2   3   5   5   7   7   8   8
20 FT wind gust.5   5   5   6   6   7   8   9   10  12  12  12
Mix hgt (kft)...0.4 0.4 0.4 1.0 1.6 2.2 2.3 2.4 2.5 2.2 1.8 1.5
Transp wind dir.SW  SW  SW  SW  SW  SW  S   S   SE  SE  SE  SE
Transp wind spd.6   6   5   6   6   6   6   7   7   8   9   10
Dispersion idx..3   2   5   7   11  16  17  20  22  23  21  19
LVORI...........8   8   7   5   4   4   3   3   3   3   3   3

$$
Forecaster...Shashy
Requested by...Jeff Darr
Type of request...PRESCRIBED
.TAG 2621525.0/JAX
.DELDT 09/10/26
.FormatterVersion 2.0.0
.EMAIL jeff.darr@fdacs.gov